Machine for grading sand.



PATENTE'D SEPT. 26, 1905.

C. W. PALMER. MACHINE FOR GRADING SAND.

APPLICATION FILED JUNE. 4. 1904.

3 SHEETS-SHBBT 1.

PATENTED SEPT. 26, 1905. O. W. PALMER.

MACHINE FOR GRADING SAND.

APPLICATION FILED JUNE 4, 1904.

3 SHEETSSHEET 2.

No. 800,480. PATENTED SEPT. 26, 1905. C.-W. PALMER.

MACHINE FOR GRADING SAND.

APPLICATION FILED JUNE 4.1904.

SHEETS-SHEET 3.

UNITED STATES PATENT QFFICE.

CHARLES IV. PALMER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO FRANK H. CAVEN AND JAMES CAVEN, OF PHILADELPHIA, PENNSYL- VANIA, TRADING UNDER THE FIRM, STYLE AND TITLE OF JAMES CAVEN & SON.

MACHINE FOR GRADING SAND.

Specification of Letters Patent.

Patented Sept. 26, 1905.

Application filed June 4, 1904. Serial No. 211,198.

To aZZ whom it may concern.-

Be it known that I, CHARLES W. PALMER, a

citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Machines for Grading Sand, of which the following is a specification. One object of my invention is to provide an lmproved machine for grading fine granular material, such as sand, and which shall be capable of delivering a product containing any desired percentages of particles of different sizes.

A further object of the invention is to provide an efiicient and inexpensive machine for continuously removing from granular material all particles less than a certain predetermined fineness.

These, together with other advantageous results, I attain as hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 is a side elevation, to some extent diagrammatic, illustrating one arrangement of apparatus for grading sand according to my invention. Fig. 2 is a side elevation, partly in section, of one of the separatinghoppers employed in connection with my in- Vention, the same being illustrated as provided with two sets of upwardly-pointing nozzles instead of one set, as in the'hoppers shown in Fig. 1. Fig. 3 is a plan view of the piping for the sets of nozzles, known as the agitator, employed in carrying out my invention. Fig. 4 is a plan View, to some extent diagrammatic, showing an arrangement of apparatus for returning a certain proportion of fine material to the finished product, and Fig. 5 is a side elevation of the apparatus shown in Fig. 4:.

Hitherto great difficulty has been experienced in grading fine granular material, such as sand, in commercial quantitiesthat is, in separating a given body of sand into masses of definite degrees of fineness. It will be understood that it is frequently desirable to procure a body of sand which, for example, shall be of a certain fineness or which shall contain definite and predetermined percentages of particles of different fineness, and this has hitherto been commercially impossible, owing to the difliculty of treating large bodies of sand at any but a cost which would be prohibitive. The objection to accomplishing this end by the use of screens is due principally to the fact that the meshes of the screens become very quickly clogged, particularly when the material treated is of a fineness ranging from a size which would pass a No. 1O sieve and be retained upon a No. 80 sieve.

I have found it possible to grade sand, even of the finest, in any desired manner by exposing the same to the action of a current of water whose pressure and velocity could be so varied as to carry away all material finer than a certain definite size, the sand being subjected to treatment in one or any desired number of receptacles in order to satisfactorily accomplish this end. If it is desired that there shall be a certain proportion of line material in a certain body of sand, I provide means whereby some of the fine material removed at the beginning of the operation is returned to the sand at another period of its treatment.

In carrying out my invention I prefer to employ the apparatus shown in Fig. 1, in which A represents a receiving-hopper placed to discharge its contents into a conveyer B, which transfers the sand or other material treated to a slide or chute b. Said conveyer and a large portion of the apparatus hereinafter described is carried upon a framework A, which supports a rotary double screen G, into which the chute b discharges. A water-supply pipe Z) is placed to deliver water upon this chute, so as to facilitate the flow of sand into the inner rotary screen 0, which forms apart of the screen (l. A chute 0 receives material delivered from the interior of the rotary screen 0, while a chute 0 receives that delivered from the screen C, the liner particles which pass through said latter sieve falling upon a slide or chute 0", which in turn delivers material upon a chute a. This latter discharges the sand into the first of a series of hoppers I) D, &c., preferably of the construction illustrated in Fig. 2, and provided with a Weir or overflow edge (Z, as indicated in Fig. 1. Each of the hoppers has attached to its lower portion a discharge-pipe cZ, provided with a contracted throat. (Z and a nozzle (Z connected to a supply-main cl and placed so as to deliver a jet of water into said throat (Z Supported ata slightdistance above the bottom of each hopper are one or more series of upwardly-pointed nozzles d, projecting from a U-shaped pipe connected to a conduit (7 of suitable size, and it will be noted that said pipe for the nozzles is preferably arrai'iged around or adjacent to the sides of the hopper, so as to permit of the downward passage of sand between its arms. The pipe 6! from the hopper D is extended upwardly, so as to discharge into the top of the hopper I), and the pipe (Z from this latter hopper in turn discharges into the hopper D A hopper D receives material from the discharge-pipe a of the hopper D and there is a conveyerE for removing the sand "from said first hopper to any desired chute (not shown) for delivery to a stock-pile or to any receiving vessel.

IVhile in Fig. 2 I have shown the supplypipe (5 to the agitators extending upwardly through the hopper and over its edge, it may, if desired, be extended through the side of the hopper, and all of these pipes (Z are connected to a supply-main f, which in turn is supplied with water from a pump F. The jet-supply pipes at are connected to a supply-main g, to which water is delivered from a pump G.

Under operating conditions sand is taken from the hopper A by the conveyer B and is delivered to the interior screen 0. Foreign matter, such as roots or large stones, &c., passes from this screen to the chute 0, while the material passing through this screen is still further divided, since part of it passes through the finer screen C, while another portion passes 03 into the chute 0 It will be understood that water is constantly furnished to these screens from the pipe I), so that material capable of passing a No. 10 screen, for instance, is delivered upon the chutes 0 and c' and flows freely into the hopper D. ater is continuously delivered under pressure in this and in the two other hoppers D and D by means of the agitators formed by the various u pwardly-di scharging nozzles (Z and as this water passes away from the hopper over the weir (Z it carries with it the mud and a certain proportion of the dust or very finest particles found in the sand. The heavier particles sink to the bottom of the hopper, where they are propelled by a jet of water delivered from the nozzle (Z through the pipe d and discharged into the hopper D. In this second hopper the water delivered by the agitator may, if desired, be at a higher pressure than that delivered by the agitator in hopper D, as determined by the amount of opening of a valve 1]" in the pipe cl, so that a still further portion of the fine material in the sand will be carried away by the overflowwater from this second hopper, while the remainder is propelled by the water-jet at the bottom of the hopper through the dischargepipe (Z and is delivered to the hopper D Here again it is subjected to upwardly-discharging jets of an agitator, which, as before, may deliver water at a higher pressure than that in the other hoppers or, if desired, may be at the same pressure. In any case a still further amount of fine material, of a larger grade, however, than before, will be separated from the sand as it falls to the bottom of the hopper, and this latter is linally delivered into the hopper D, from whence it is taken by the conveyor E. By throttling the water delivered to the agitators or by varying the pressure of the water in the main 7 by suitably governing the pump F material of any desired grade may be separated from that passing through the various hoppers and afterward returned to the hopper D so that the sand in said hopper can be made to contain any desired proportion of particles of various sizes-that is, it will consist of sand small enough to pass the screen G and having any desired proportion of relatively fine particles.

It will be understood that, if desired, the exceedingly fine material carried away by the overflow of water from any one or a number of the hoppers D, &c., may be saved for use by itself or for future mixture with sand of other grades, the particular case illustrated in Fig. 1 being one in which the finest grade of material is not desired for use.

In order to obtain a product composedol a mixture of relatively coarse and relatively fine sand which shall be free of intermediate sizes of material, I preferably employ the arrangement of apparatus shown in Figs. 4 and 5, in which the hoppers D, D, and D are provided with troughs m, m, and m respec tively, for the reception of water escaping from said hoppers, These troughs all discharge into a waste-chute m and in addition have each a gate or valve 221* opening into a chute m, which discharges into a hopper m. This latter is provided with a water-jet conveyer m similar to that used in connection with the hoppers D, &c., and by said conveyer material is delivered into the hopper D Under operating conditions three different grades or material are discharged by the three hoppers D, D, and D through the troughs m, m, and m into the chute 717i, while a fourth grade, composed mostly of coarser material, is delivered into the final hopper D. If now it is desired that the finished product shall contain a larger percentage of very fine material than would be the case under ordinary conditions, the gate on," is opened, so that the water overflowing from the hopper D is delivered into the chute mi, and since this water carries with it a large proportion of the very fine material contained in the sand delivered from the screen C said material after passing to the hopper m is discharged into and mixed with the finished product in the hopper D. It is obvious that the amount of this fine materialso added may be very closely regulated by means of the slide or gate m and also that various proportions of coarser material may be similarly added by suitable manipulation of the gates mi in the troughs m and m If desired, water-jets on may be employed to facilitate the How through the trough 'm' Instead of regulating the .pressure of water delivered by the agitators to vary the grade of material carried away by the water in any one of the hoppers I may attain the same end by adjusting the heights of the various weirs (Z as illustrated in Fig. 1. On the other hand, there may be more than one set of agitators to each hopperfor example, as shown in Fig. 2, where the second set of nozzles (Z are arranged around the sides, so as to increase the violence of the water action on the sand under treatment.

I claim as my invention 1. The combination of a series of containers each having a conduit for liquid overflowing therefrom, means for conveying material from the bottom of each container and discharging it into another container, a receptacle for the finished product, a conduit connecting the'overflow-conduits with said receptacle, and another conduit connecting the lower portion of the last container of the series with the receptacle,with adjustable means for directing the material from the overflowconduit of any container into the conduit to said receptacle, substantially as described.

2. The combination of a series of containers each having a conduit for liquid overflowing therefrom, means for conveying material from the bottom of each container and discharging it into another container, a receptacle for the finished product, a conduit connecting the overflow-conduits with said receptacle, another conduit connecting the lower portion of the last container of the series with the receptacle, hydraulic means for causing How of liquid through said last conduit, means for separately discharging the grades from the containers, and adjustable means for diverting any number of said grades from the overflow-conduits to the conduit connecting with said receptacle, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES W. PALMER.

Witnesses:

WILLIAM E. BRADLEY, J os. H. KLEIN. 

